Molybdenum-antimony catalysts for hydrocarbon treating

ABSTRACT

HYDROCARBONS ARE HYDROCRACKED AND DESULFURIZED BY CONTACTING WITH SUPPORTED MOLYBDENUM-ANTIMONY CATALYSTS.

United States Patent 01 Tree Patented July 18, 1972 Int. Cl. Cg 13/02, 13/04 US. Cl. 208-109 9 Claims ABSTRACT OF THE DISCLOSURE Hydrocarbons are hydrocracked and desulfurized by contacting with supported molybdenum-antimony catalysts.

This invention relates to the use of molybdenum-antimony catalysts for hydrocarbon treating.

In one of its more specific aspects, this invention relates to a process of treating parafiinic hydrocarbons with a supported molybdenum-antimony catalyst for the purpose of hydrocracking and/ or desulfurizing.

According to this invention there is provided a method for hydrotreating hydrocarbons to hydrocrack and/or desulfurize the hydrocarbon by contacting the hydrocarbon with hydrogen and with a supported catalyst comprising molybdenum and antimony. V

The method of this invention is applicable to heavy hydrocarbon-containing feedstocks such as crude oil, heavy mina gel powder and the resulting mixture pelletized and calcined. l 7' i i Calcination procedures are those conventionally employed in catalyst preparation and involve maintaining the catalyst at temperatures of 900-1400 F. for about 0.1 to about 24 hours. Thereafter, reduction in hydrogen is carried out at 500 to 1400 F. for about 0.1 to about 24 hours.

After the catalyst has been spent in the process, it can be regenerated by calcination in air and reduction in hydrogen under the aforestated conditions. I

The method of this invention is carried out by contacting the feedstock, in either the liquid or vapor phase, with hydrogen and with the catalyst at a pressure within the range of from about 100 to about 1500 p.s.i.g., and prefresidual fractions and heavy lubricating oil fractions derived therefrom. The process is particularly applicable when these feedstocks are paraflinic or contain a substantial paraflinic content, and is applicable to paraflins having as few as six carbon atoms per molecule. If employed for desulfurization, the method can be carried out using heavy aromatics as feedstocks.

The catalysts which are employed by the method of this invention are comprised of supported molybdenum and antimony. The molybdenum is present in an amount within the range from about 3 to about 15 weight percent of the total catalyst composition. Preferably, it will be present from about 7 to about 10 weight percent.

The antimony is present in an amount such that the weight ratio of molybdenum to antimony will be within the range of from about 3 to 1 to about 1 to 1 and preferably from about 2 to 1 to about 3 to 2.

The molybdenum and antimony are generally supported on a nonacidic refractory metal oxide such as alpha-alumina, gamma-alumina, silica, calcium aluminate, magnesium oxide and their mixtures. Such supports are typical catalytic grade materials and will have a surface area of at least 1 m. /g., gamma-alumina and alpha-alumina are preferred supports.

The catalysts are prepared by conventional methods of aqueous impregnation of dry mixing followed by calcination. For example, aqueous solutions of suitable antimony and molybdenum salts can be slurried with the support which is thereafter dried and calcined. A paste can be formed by mixing powdered catalytic alumina with an aqueous solution comprising antimony pentachloride and ammonium molybdate. The paste is neutralized with ammonium hydroxide, dried, granulated and calcined.

Similarly, a preformed catalyst pellet can be impregnated erably about 400 to 1000 p.s.i.g. The reaction temperature is dependent upon the nature of the feedstock, feedstocks containing substantial quantities of aromatics generally being processed above about 700 F. to avoid excessive hydrogenation. Generally, however, the processing temperature will be within therange of about 650 F. to about 1000 F. 1

The hydrocarbon liquid hourly space velocity feed rate generally will be within the range of about 0.5 to about 5, preferably 1 to about 3, while the hydrogen feed rate will be within the range of about 1000 to about 4000 s.c.f. per barrel of hydrocarbon feed.

The process can be carried out either continuously or batchwise, a packed bed being preferably employed with conventional fractionation equipment being supplied to separate and recover the product. f The following examples illustrate typical methods of preparing the catalyst and of carrying out the process. While they exemplified the best mode of doing so, they are not to be considered as limiting the invention to the specific embodiments employed.

EXAMPLE I A catalyst comprising molybdenum and antimony on gamma-alumina was prepared. A mixture of 30.0 g. of molybdenum trioxide, 13.9 g. of antimony oxide and 168.4

g. or catalytic gamma-alumina gel was ball-milled for the pellets were reduced in a stream of hydrogen at about 800 F. The catalyst contained 9.9 weight percent molybdenum and 4.7 weight percent antimony.

This catalyst was employed in the process of Example II.

EXAMPLE II A portion of the catalyst prepared in Example I was employed in a packed bed for the processing of a waxy Umbarka crude oil in two runs. For comparison purposes, a similar run was carried out using a commercially available cobalt molybdate on alumina hydrotreating catalyst. This catalyst was Harshaws CoMo 0301T catalyst, this catalyst being in the form of /s" pellets and containing 8.5 weight percent M00 and 2.5 weight percent C00. It is available from Hars'haw Chemical Company, a division of Kewanee Oil Company, Cleveland, Ohio. All catalysts were activated by reduction in hydrogen before use.

f Feedstock properties, operating conditions and test results were as follows:

. 4 finished catalyst containe'dSJ 'weight percent num and 4.1 weight percent antimony.

This catalyst was employed in the method of the inmolybde- Feed Run number vention to desulfurize a highly aromatic extract oil, the stock 1 2 3 composition of which, together with the operating condigatalm ar n w 0) Harshaw lions and results, are shown below.

Fiiiii e rg t m i s59 ass 760 'QPERATING CONDITIONS giiiigipiisiigii' Gui 40(1) Feedstock LHSV 1 fi fi ffii f ig'lgfirgg Hydrogen charge rate, s.c.f./bbl. 4300 weight percent of feed 84.0 86.0 82.5 Temperature, F 300 Liquid product; Pressure, p.s.i.g 600 Analysis: Liquid Pour point, F 70 32 32 6t Feedstock product Cloud point,F 70 32 32 48 r Gravity,API 44.7 44.6 46.3 51. Analysls: Total sulfur, ppm... 300 5 4 Gravity, APL. 9. 2 11. 6 Carbon, weight percent 88. 8 89. at 1 Invention. Hydrogen, weight percent- 8. 8 8. 9 1 Undetermined. Total sullur,weight percent 2. 09 0. 97 3: 5: 3 fi igg igi giggigg 232$}: 2 21: 52 These data illustrate the effectiveness of the method of substantially reduced pour point as compared to that of the Present mventlon the crude oil and produced a liquid differing little in h meflmd the f i was emifhyed to cleave gravity from that of the crude oil. Comparatively, Run 3 parafiins by hydrogenolysls m the followmg evample produced a liquid product having a higher pour point 25 EXAMPLE V sis sitsaiszssfsns2s:is: szsas A that in 1v the Wax components of the crude on than is the used in the hydrogenolysis of n-hexadecane. Operating conditions and results were as follows: mercial catalyst.

Also, the sulfur analysis shows that the invention proc- OPERATING CONDITIONS ess is effective for desulfurization. Feed HeXadecane EXAMPLE III Feed rate, LHSV 1 Catalysts similar to those prepared in Example I, some Hy rogen r 1110168/ 111016 feed 8 supported on gamma-alumina having a surface area of T mp r r F- 321 100-200 m. /g. and some supported on predominantly Press r p- -i-g 400 alpha-alumina which had been a high surface alumina RESULTS heat-treated to reduce its surface to about 6 m. /g., were employed in the treating of a waxy lube oil fraction. This Cpmerslon P fraction has a melting point of about 140 F. and an API 40 Yi ld moles c converted to product per 100 gravity of moles converted:

In all runs, the fraction was charged at a LHSV of 1 (3 and lighter 13,55 with the hydrogen rate being 1600 s.c.f./bbl. C 7 47 Other operating conditions and results of the runs were '(3 314 as shown below. Runs 4, 5, 6 and 7 were carried out 3., 12,1 using the high surface area gamma-alumina and Runs 8, C 8,10 9 and 10 employed the low surface area alpha-alumina. C 3 )4 c I 8.06 Run Number G -C15 4 5 6 7 s 9 10 0 tin Edition 1 tal 100- 7 PBIB ECO S @fi if iifljfgff 233 23g 23g 286 i5, 1%? The above data illustrate the effectiveness of the Recovery, llquidasw i nt method of this invention 1n hydrocracking paraflins. Li Percent feed Relatedly, in a similar test in which thiophene had been quid product analy p ravity, 45.7 41.0 40.6 38.0 37.8 incorporated 1n n-hexane to the extent of about 15 weight Cloudminb" F 48 85 93 95 33 percent,'the hydrocracked efiiuent from the reaction zone The above data illustrate that the process of the inven- 2132; 21 31:122 31 i liii fgregoing that various tion subsfantiany reduces Wax content shown by modifications can be made to the method of this inventhe relatlvely cloud Points over Wlde range. of 0 tion. Such, however, are considered as being within the operating conditions. Scope of the invention In the following example a highly aromatic, high sul- What is daimed is: s; was treated accordlng to the method of the 1. A method of hydrotreating hydrocarbons to hydroven crack and desulfurize said hydrocarbons which comprise EXAMPLE IV v contacting saict hydrocarbon with a supported catalyst A catalyst was prepared by forming a paste of g. of consisting essentially of molybdenum, and antimony and finely divided, flame-hydrolyzed alumina (Alon-C) and a wi y fi df Ifiwvefig' the hydfotl'eflted p u 'solution prepared from 14.8 g. of (NH )5Mo O -H O 2. The methodfof claim 1 in ,which a substantially and 8 ml. of SbCl in 250 ml. water. The paste was ad- 7 parafinic hydrocarboncontaining at least 6 carbon atoms justed'to a pH of about 8 by the addition of 33 ml. of a 28 70 is contacted with 'said catalyst comprising molybdenum and antimony, said molybdenum being present in the amount in the range of from about 3 to about 15 weight percent of said catalyst and said antimony being present in an amount in the range of from about 1 to about /3 part per part by weight of said molybdenum at a temperature in the range of from about 650 F. to about 1000 F. at a pressure in the range of about 100 to about 1500 p.s.i.g., the feed rate of said hydrocarbon being in the range of from about 0.5 to about LHSV, said hydrogen feed rate being in the range of from about 1000 to about 4000 s.c.f./bb1. of said hydrocarbon.

3. The method of claim 2 in which said supported catalyst is supported on a material selected from the group consisting of alpha-alumina, gamma-alumina, silica, calcium aluminate, magnesium oxide and mixtures thereof, said material having a surface area of not less than 1 m. /g.

4. The method of claim 1 in which a substantially aromatic hydrocarbon comprising sulfur is contacted with said catalyst comprising molybdenum and antimony, said molybdenum being present in an amount in the range of from about 3 to about 15 weight percent of said catalyst and said antimony being present in an amount of from about /3 to 1 to about 1 to 1 parts per part by weight of said molybdenum at a temperature in the range of from about 700 F. to about 1000 F. at a pressure in the range of about 100 to about 1500 p.s.i.g., the feed rate of said hydrocarbon being in the range of from about 0.5 to about 5 LHSV, said hydrogen feed rate being in the range of from about 1000 to about 4000 s.c.f./bbl. of said hydrocarbon.

5. The method of claim 1 in which said molybdenum and said antimony are contained in said catalyst in a weight ratio of molybdenum to antimony within the range of about 3 to 1 to about 1 to 1.

6. The method of claim 1 in which said supported catalyst is produced by combining molybdenum oxide and antimony oxide with a support, calcining the combination and reducing the calcined combination.

7. The method of claim 6 in which said supported catalyst is produced by impregnating a support with aqueous solutions of antimony and molybdenum salts, calcining the impregnated support and reducing the calcined support.

8. The method of claim 1 in which said catalyst is regenerated after said hydrotreating.

9. The method of claim 8 in which said catalyst is regenerated by calci-nation in air and reduction in hydrogen.

References Cited UNITED STATES PATENTS 3,099,617 7/ 1963 Tulleners 208109 3,390,074 6/1968 Mulaskey 252--456 2,944,005 7/1960 Scott 208l09 3,117,074 1/1964 Honerkamp et a1. 208-109 X 3,536,632 10/1970 Kroll 208109 X TOBIAS E. LEVOW, Primary Examiner P. F. SHAVER, Assistant Examiner US. Cl. X.R. 

